Restructuring and Asset Impairment Charges (Components of Restructuring Charges and Segment Allocation) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Restructuring Cost and Reserve [Line Items]
Severance and other charges	$ 28	$ 7	$ 26
Lease related charges	2	0	1
Fixed asset write-offs	1	0	0
Reversal of restructuring accruals	(1)	(1)	(1)
Total restructuring charges	30	6	26
Restructuring charges	30	6	26
Water Infrastructure
Restructuring Cost and Reserve [Line Items]
Restructuring charges	17	5	19
Applied Water
Restructuring Cost and Reserve [Line Items]
Restructuring charges	10	1	6
Sensus
Restructuring Cost and Reserve [Line Items]
Restructuring charges	1	0	0
Corporate and other
Restructuring Cost and Reserve [Line Items]
Restructuring charges	$ 2	$ 0	$ 1